Now because OMXPlayer is still very new, it is still very basic. So basic in fact it's key bindings (for play/pause/stop/quit) only function if the program is launched via the CLI. Knowing my Fiance and friends who often use the media PC would give me no end of grief if they had to open a terminal to play movies - I set about finding a solution. Today I'd like to share that fairly simple solution with you!
To allow users to simply "double click" on a media file via the file manager and have it open in OMXPlayer you need to create a .desktop file for OMXPlayer. Open a terminal on your pi and run:
sudo nano /usr/share/applications/omxplayer.desktop
For it's contents paste:
Exec=omxplayer -o hdmi %f
Save and close the file (ctrl+x in nano) and you should be good to go! When you double click on a media file in your file browser simply select Open With: OMXPlayer! Please note some users have reported this doesn't work with LXDE - I cannot confirm this though as I only use E17 and it works fine there :)